1. Field of the Invention
The present invention generally relates to a seat belt restraint system for restraining a seated occupant in the motor vehicle. More specifically, the present invention relates to a vehicle seat belt guiding device for guiding a shoulder belt portion of a seat belt restraint system.
2. Background Information
Most motor vehicles that are driven on a public road are required to have a seat belt restraint system for restraining a seated occupant. A variety of passive seat belt restraint systems have been proposed and put into practical use. Typically, a passive seat belt restraint system has seat belt webbing that restrains the seated occupant in both an area generally corresponding to the occupant's lap and an area generally corresponding to the occupant's torso. The seat belt webbing has a first end fixedly attached to the vehicle at a first point and a second end fixedly attached to the vehicle at a second point, with an intermediate portion of the seat belt webbing slidably attached to the vehicle at a third point by a D-ring.
Usually, the above mentioned seat belt restraint system has a retractor that is attached to one end of the seat belt webbing. The retractor includes a spool that receives the seat belt webbing for retraction or pay-out of seat belt webbing. The spool is used to wind up and store the seat belt webbing when the seat belt is not being used. Generally, the spool is also designed to payout the seat belt webbing until detection of an impact situation. In the case of an impact situation, the spool is locked to restrain the occupant via the seat belt.
Recently, retractors have also been designed to include a pretensioner, which is operatively coupled to the spool for taking up the seat belt webbing and eliminating slack when a potential impact situation is detected. In other words, the pretensioner of the retractor rapidly retracts the seat belt webbing onto the spool in response to a sensor detecting an impact situation to eliminate any slack in the seat belt, and thus, controls the physical space between the occupant and the seat belt webbing. In this manner, the occupant of the seat is pulled tightly into the seat before an impact situation arises in which the occupant moves forwardly relative to the seat. Also, retractors have been designed having one or more force limiting elements which are structured to allow the spool to rotate and payout the seat belt webbing upon reaching predetermined force levels between the occupant and seat belt. In this manner, the restraining force imposed on the occupant by the seat belt webbing can be limited in a controlled manner.
Typically, the D-ring is pivotally mounted so that the D-ring rotates from a seat belt stowed position to a seat belt in-use position. During a pretensioning situation (e.g., an impact situation) of the seat belt webbing, a force to the seat belt webbing tends to cause the D-ring to rotate downwardly. Once the D-ring stops rotating during a pretensioning, the seat belt webbing can slide along the guide slot of the D-ring such that bunching of the seat belt webbing can occur at one end of the guide slot of the D-ring. On the other hand, during payout situation of the seat belt webbing, a force from the seat belt webbing tends to cause the D-ring to rotate upwardly. Once the D-ring stops rotating during payout situation, the seat belt webbing can slide along the guide slot of the D-ring such that bunching of the seat belt webbing can occur at one end of the guide slot of the D-ring.
In view of the above, it will be apparent to those skilled in the art from this disclosure that there exists a need for an improved a vehicle seat belt guiding device. This invention addresses this need in the art as well as other needs, which will become apparent to those skilled in the art from this disclosure.